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MRCOOL DIY Mini Split - 42,000 BTU 4 Zone Ductless Air Conditioner and Heat Pump, DIY-B-436HP09091212

SKU DIY-B-436HP09091212
by MRCOOL
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$5,794.60

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Description

MRCOOL DIY Mini Split - 42,000 BTU 4 Zone Ductless Air Conditioner and Heat Pump, DIY-B-436HP09091212

Step into a new era of climate control with the MRCOOL DIY Mini Split 42,000 BTU 4 Zone system — a game-changer for contractors, business owners, and HVAC professionals who demand efficiency, power, and simplicity. Imagine offering your clients complete comfort across multiple rooms, with a system designed to handle the toughest conditions while being incredibly easy to install. This is the perfect solution for homes, garages, workshops, and commercial spaces that need reliable, year-round temperature control without the hassle of complicated setups.

Powerful and Durable Performance

At the heart of this system is a robust 36,000 BTU condenser, engineered to withstand harsh environments thanks to its Gold Fin® coating that protects against corrosion — a must-have for coastal or demanding locations. With an industry-leading 21.5 SEER2 and 8.5 HSPF-5 rating, this unit delivers exceptional energy efficiency, helping your customers save on utility bills while enjoying powerful cooling and heating. Even when temperatures plunge to -13°F, this system keeps the warmth flowing, ensuring comfort no matter how cold it gets outside.

Perfectly Sized Air Handlers for Every Room

Visualize your customers enjoying tailored comfort in every space with two air handler options:

  • The 9,000 BTU Air Handler is ideal for smaller rooms between 180 and 375 square feet — think bedrooms, home offices, or cozy corners where consistent comfort is key.
  • The 12,000 BTU Air Handler covers medium-sized rooms from 376 to 500 square feet, perfect for living rooms, workshops, or larger spaces that require steady, efficient climate control.

Each air handler supports multiple modes including COOL, HEAT, AUTO, DRY, and SLEEP, allowing your clients to customize their environment effortlessly, day or night.

Installation Made Effortless

Imagine reducing installation time and complexity dramatically. Thanks to MRCOOL’s patented Pre-Charged Quick Connect Line Sets, you can install this system without vacuum pumps, refrigerant handling, or special tools. The lightweight, compact air handlers make mounting quick and simple, so you can complete jobs faster and move on to the next project with confidence.

Smart Control for Modern Convenience

Your customers will appreciate the convenience of the SmartHVAC app, which puts full system control right in their hands — from anywhere in the world. Whether adjusting temperature, switching modes, or setting schedules, remote management adds a modern, tech-savvy edge that enhances user satisfaction and builds loyalty.

Why Choose the MRCOOL DIY Mini Split 42,000 BTU 4 Zone?
  • DIY-friendly installation with patented Pre-Charged Quick Connect Line Sets — no vacuum pumps or refrigerant charging needed
  • Durable Gold Fin® coated condenser protects against corrosion and extends system life
  • Exceptional energy efficiency with 21.5 SEER2 and 8.5 HSPF-5 ratings to lower operating costs
  • Reliable heating performance down to -13°F outdoor temperature
  • Versatile air handlers sized for small to medium rooms with multiple climate modes
  • SmartHVAC app compatibility for remote, convenient control
  • Comprehensive warranty: 7 years on the compressor and 5 years on parts

With the MRCOOL DIY Mini Split 42,000 BTU 4 Zone system, you’re not just installing HVAC equipment — you’re delivering peace of mind, comfort, and control to your customers, all while maximizing your efficiency and profitability. This system lets you build a reputation for quality, reliability, and innovation, project after project.

Condenser (36K BTU)

  • Innovative Installation: Experience seamless installation with MRCOOL’s patented Pre-Charged Quick Connect Line Sets, ensuring a hassle-free process without needing a technician.
  • Corrosion Resistance: Shield your system from coastal elements with the robust Gold Fin® condenser coating.
  • Energy Efficiency: Save on energy with an impressive 21.5 SEER2 and 8.5 HSPF-5 rating.
  • Extreme Performance: Heat efficiently even when temperatures plunge to -13°F.
  • Reliable Warranty: Enjoy peace of mind with a 7-year compressor warranty and a 5-year parts warranty.

Air Handler (9K BTU)

  • Versatile Climate Control: Whether you're in the mood for COOL, HEAT, AUTO, DRY, or SLEEP, these Air Handlers ensure comfort year-round.
  • Perfect Room Coverage: Optimized for spaces ranging from 180 to 375 square feet, perfect for smaller spaces and cozy corners.
  • Smart Control Anywhere: Take command with SmartHVAC app compatibility, offering fingertip convenience from anywhere on the planet.
  • Effortless Installation: The compact and lightweight design makes mounting quick and simple, minimizing installation efforts.
  • Quick Connect System: With MRCOOL’s Pre-Charged Quick Connect Line Set, you can set up easily—no vacuuming or complex tools required!

Air Handler (12K BTU)

  • Versatile Climate Control: Enjoy personalized comfort with COOL, HEAT, AUTO, DRY, or SLEEP modes to suit any season or preference.
  • Perfect Room Coverage: Tailored for areas ranging from 376 to 500 square feet, ideal for medium-sized spaces.
  • Smart Control Anywhere: Take advantage of SmartHVAC app compatibility, giving you complete control remotely.
  • Effortless Installation: A compact and lightweight design allows for hassle-free mounting and setup.
  • Quick Connect System: Thanks to the MRCOOL Pre-Charged Quick Connect Line Set, installation is incredibly simple—no professional vacuuming needed!
Shipping and Return

For Shipping & return information visit here

COVERAGE AREA

HIVE WARRANTY

HVAC Hive Warranty Information:

HVAC Hive is an authorized dealer for every product on our website. Every HVAC system and component comes with its original manufacturer's warranty, guaranteeing you receive a functional, quality product.

Our 5-Year Parts & Labor Warranty Promise: We go beyond the standard coverage. If a manufacturer's warranty doesn't cover your product for a full 5 years, HVAC Hive will extend both parts and labor warranty to complete the 5-year coverage period.

Example: If your manufacturer covers 2 years parts & labor, we'll cover an additional 3 years — giving you a full 5 years of parts and labor protection.

Warranty Coverage Includes:

  • Parts replacement for manufacturing defects
  • Labor costs for covered repairs
  • System malfunctions and component failures

Warranty Details:

  • Residential, light commercial, and full commercial warranties vary based on your usage
  • Specific warranty terms and coverage periods are listed on each product page
  • Both parts and labor are covered under our extended warranty program

Making a Warranty Claim: Contact our Worker Bee Support team at 1-888-712-2465 or karim@hvachive.com . We'll handle your claim quickly and professionally, covering both parts and labor costs. You can also contact the manufacturer directly if preferred.

Questions? Need help understanding your parts & labor warranty coverage? Our team is here to explain the details and ensure you're fully protected.

Contact US

Product Overview

  • Zone / ROOM:

    Zone / ROOM: 4 Zone

  • Air Handler BTU:

    Air Handler BTU: 9k + 9k + 12k + 12k

  • Condenser BTU:

    Condenser BTU: 36k

  • Outdoor Operating Temp (Cool/ heat):

    Outdoor Operating Temp (Cool/ heat): Heating -13°F to 75.2°F & Cooling 5°F to 122°F

  • Warranty

    Warranty 7-year compressor & 5-year parts warranty

Description

MRCOOL DIY Mini Split - 42,000 BTU 4 Zone Ductless Air Conditioner and Heat Pump, DIY-B-436HP09091212

Step into a new era of climate control with the MRCOOL DIY Mini Split 42,000 BTU 4 Zone system — a game-changer for contractors, business owners, and HVAC professionals who demand efficiency, power, and simplicity. Imagine offering your clients complete comfort across multiple rooms, with a system designed to handle the toughest conditions while being incredibly easy to install. This is the perfect solution for homes, garages, workshops, and commercial spaces that need reliable, year-round temperature control without the hassle of complicated setups.

Powerful and Durable Performance

At the heart of this system is a robust 36,000 BTU condenser, engineered to withstand harsh environments thanks to its Gold Fin® coating that protects against corrosion — a must-have for coastal or demanding locations. With an industry-leading 21.5 SEER2 and 8.5 HSPF-5 rating, this unit delivers exceptional energy efficiency, helping your customers save on utility bills while enjoying powerful cooling and heating. Even when temperatures plunge to -13°F, this system keeps the warmth flowing, ensuring comfort no matter how cold it gets outside.

Perfectly Sized Air Handlers for Every Room

Visualize your customers enjoying tailored comfort in every space with two air handler options:

  • The 9,000 BTU Air Handler is ideal for smaller rooms between 180 and 375 square feet — think bedrooms, home offices, or cozy corners where consistent comfort is key.
  • The 12,000 BTU Air Handler covers medium-sized rooms from 376 to 500 square feet, perfect for living rooms, workshops, or larger spaces that require steady, efficient climate control.

Each air handler supports multiple modes including COOL, HEAT, AUTO, DRY, and SLEEP, allowing your clients to customize their environment effortlessly, day or night.

Installation Made Effortless

Imagine reducing installation time and complexity dramatically. Thanks to MRCOOL’s patented Pre-Charged Quick Connect Line Sets, you can install this system without vacuum pumps, refrigerant handling, or special tools. The lightweight, compact air handlers make mounting quick and simple, so you can complete jobs faster and move on to the next project with confidence.

Smart Control for Modern Convenience

Your customers will appreciate the convenience of the SmartHVAC app, which puts full system control right in their hands — from anywhere in the world. Whether adjusting temperature, switching modes, or setting schedules, remote management adds a modern, tech-savvy edge that enhances user satisfaction and builds loyalty.

Why Choose the MRCOOL DIY Mini Split 42,000 BTU 4 Zone?
  • DIY-friendly installation with patented Pre-Charged Quick Connect Line Sets — no vacuum pumps or refrigerant charging needed
  • Durable Gold Fin® coated condenser protects against corrosion and extends system life
  • Exceptional energy efficiency with 21.5 SEER2 and 8.5 HSPF-5 ratings to lower operating costs
  • Reliable heating performance down to -13°F outdoor temperature
  • Versatile air handlers sized for small to medium rooms with multiple climate modes
  • SmartHVAC app compatibility for remote, convenient control
  • Comprehensive warranty: 7 years on the compressor and 5 years on parts

With the MRCOOL DIY Mini Split 42,000 BTU 4 Zone system, you’re not just installing HVAC equipment — you’re delivering peace of mind, comfort, and control to your customers, all while maximizing your efficiency and profitability. This system lets you build a reputation for quality, reliability, and innovation, project after project.

Condenser (36K BTU)

  • Innovative Installation: Experience seamless installation with MRCOOL’s patented Pre-Charged Quick Connect Line Sets, ensuring a hassle-free process without needing a technician.
  • Corrosion Resistance: Shield your system from coastal elements with the robust Gold Fin® condenser coating.
  • Energy Efficiency: Save on energy with an impressive 21.5 SEER2 and 8.5 HSPF-5 rating.
  • Extreme Performance: Heat efficiently even when temperatures plunge to -13°F.
  • Reliable Warranty: Enjoy peace of mind with a 7-year compressor warranty and a 5-year parts warranty.

Air Handler (9K BTU)

  • Versatile Climate Control: Whether you're in the mood for COOL, HEAT, AUTO, DRY, or SLEEP, these Air Handlers ensure comfort year-round.
  • Perfect Room Coverage: Optimized for spaces ranging from 180 to 375 square feet, perfect for smaller spaces and cozy corners.
  • Smart Control Anywhere: Take command with SmartHVAC app compatibility, offering fingertip convenience from anywhere on the planet.
  • Effortless Installation: The compact and lightweight design makes mounting quick and simple, minimizing installation efforts.
  • Quick Connect System: With MRCOOL’s Pre-Charged Quick Connect Line Set, you can set up easily—no vacuuming or complex tools required!

Air Handler (12K BTU)

  • Versatile Climate Control: Enjoy personalized comfort with COOL, HEAT, AUTO, DRY, or SLEEP modes to suit any season or preference.
  • Perfect Room Coverage: Tailored for areas ranging from 376 to 500 square feet, ideal for medium-sized spaces.
  • Smart Control Anywhere: Take advantage of SmartHVAC app compatibility, giving you complete control remotely.
  • Effortless Installation: A compact and lightweight design allows for hassle-free mounting and setup.
  • Quick Connect System: Thanks to the MRCOOL Pre-Charged Quick Connect Line Set, installation is incredibly simple—no professional vacuuming needed!
Shipping and Return

For Shipping & return information visit here

COVERAGE AREA

HIVE WARRANTY

HVAC Hive Warranty Information:

HVAC Hive is an authorized dealer for every product on our website. Every HVAC system and component comes with its original manufacturer's warranty, guaranteeing you receive a functional, quality product.

Our 5-Year Parts & Labor Warranty Promise: We go beyond the standard coverage. If a manufacturer's warranty doesn't cover your product for a full 5 years, HVAC Hive will extend both parts and labor warranty to complete the 5-year coverage period.

Example: If your manufacturer covers 2 years parts & labor, we'll cover an additional 3 years — giving you a full 5 years of parts and labor protection.

Warranty Coverage Includes:

  • Parts replacement for manufacturing defects
  • Labor costs for covered repairs
  • System malfunctions and component failures

Warranty Details:

  • Residential, light commercial, and full commercial warranties vary based on your usage
  • Specific warranty terms and coverage periods are listed on each product page
  • Both parts and labor are covered under our extended warranty program

Making a Warranty Claim: Contact our Worker Bee Support team at 1-888-712-2465 or karim@hvachive.com . We'll handle your claim quickly and professionally, covering both parts and labor costs. You can also contact the manufacturer directly if preferred.

Questions? Need help understanding your parts & labor warranty coverage? Our team is here to explain the details and ensure you're fully protected.

Contact US

Commercial HVAC PROS!

Unlock Installer Benefits Now:

  • ✓ Exclusive BULK Pricing
  • ✓ Limited Time Deals
  • ✓ Unmatched Service & Support
  • ✓ Technical support
  • ✓ Extended Warranty & Maintenance
"Their technical expertise in commercial HVAC systems is outstanding. From equipment selection to installation support, they provided everything we needed. The bulk pricing saved us thousands on our multi-building project, and their 24/7 technical support kept us running smoothly."
- Marcus R., HVAC Project Manager, 06/24

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Frequently Asked Questions about MRCOOL DIY Mini Split - 42,000 BTU 4 Zone Ductless Air Conditioner and Heat Pump, DIY-B-436HP09091212

Most Frequently Asked Questions

Yes, MRCOOL DIY mini splits are generally considered good for their easy installation, solid efficiency, and reliable performance, making them a popular choice for homeowners seeking a cost-effective, do-it-yourself solution.

A MRCOOL mini-split will typically last 12 to 20 years with proper installation and regular maintenance.

The error code DF on a MRCOOL mini split means the unit is in defrost mode—this is a normal operation where the system temporarily stops heating to melt frost from the outdoor coil, and it will automatically return to normal heating once the cycle is complete.

Other Questions

Mitsubishi is generally considered superior to MRCOOL in terms of reliability, efficiency, advanced features, and long-term durability, while MRCOOL stands out for its easy DIY installation and lower upfront cost.

The cost to install a MRCOOL mini split system typically ranges from $2,500 to $6,000 for most residential applications, depending on system size, number of zones, and whether you choose DIY or professional installation.

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Process orders within 1-2 days

Stress Free Returns

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Premum Quality

Top Tier Products, Even Better Customer Care

5 Year Warranty

We Believe In Our Products & Our Team